Attorney General Eric H. Holder Jr.’s excuses for his decision to try major terrorists in domestic courts in New York

City are becoming increasingly absurd. He should learn that sometimes the best course of action is just to admit to an exaggeration and move on.

For at least 10 months, Mr. Holder has been claiming that “our federal ‘supermax’ prisons … hold hundreds of convicted terrorists.” His logic is that if civilian trials were OK for those 300-plus convictions he claimed, they should be OK for Sept. 11 mastermind Khalid Shaikh Mohammed and other top terrorists.

Despite numerous requests from Senate Republicans for more information, the Justice Department waited until Friday, just as Congress was leaving town for a recess, finally to provide support for Mr. Holder’s assertions. At one point, the department ridiculously claimed that federal regulations precluded it from providing such a list. All along, Republican leaders made clear that they were interested only in examples of such treatment of major, high-value detainees - yet Mr. Holder never changed his claim of more than 300 convictions.

On Friday, the department finally gave Congress a list of 403 “terrorist” convictions in the past decade. Rather than bolstering Mr. Holder’s position, the data dump showed that Republicans were right to look askance at him. As it turns out, scores of those 403 convictions were for anything but major terrorism. The department included in its count all its convictions for a catchall list of potential offenses that included “animal enterprise terrorism,” “immigration fraud” and “false information and hoaxes.” Before the 10-year window covered in the data dump, an example of an “animal enterprise terrorist” was Peter Young, who pleaded guilty to unlawfully releasing minks from a Wisconsin farm. No doubt, the Department of Homeland Security would raise the terror-alert threat level to red over that.

Fifty-one of the defendants were given mere probationary sentences. Sixty-five more were minor enough to be sentenced to time already served. And 25 of the listed convictions involved only the crime of making “false statements.” An actual example not just cited but highlighted by the department was that of Akram Musa Abdallah, who in 2007 lied about having done business with the Holy Land Foundation, which three years earlier had been indicted for financially supporting the terrorist organization Hamas. Mr. Abdallah’s work with the foundation had occurred between 1994 and 1997, years before the foundation was declared a front for terror groups. Lying to the FBI is not a minor matter; it should be punished. Yet lying to hide work done 10 years earlier - work for a group that at the time pretended to be a legitimate charity - is not exactly a terrorist act of the sort about which Republicans were asking Mr. Holder.

It can be reasonable to have nonviolent civilian terrorism-related cases tried in civilian courts. Many of these cases are important in themselves, but they hardly are relevant to the question of whether dangerous foreign suspected terrorists such as Khalid Shaikh Mohammed should be able to claim American “due process” violations.